This proposal describes a five-year training program for the development of a career in clinical research, focused on improving the quality of cardiac catheterization in children. This proposal is will serve as a vehicle to developing into an independent investigator. To that end, we have established a training plan that includes mentoring, course-work, didactic educational activities, and hands-on research. Steven Kawut, MD, MS, (the primary mentor) is a tenured Associate Professor of Medicine and Epidemiology. He has a track record of successfully mentoring fellows and junior faculty and holds a K24 to support his mentoring activities. An advisory committee has been assembled to guide the candidate's career development. The application focuses on three specific aims. First, metrics to compare the outcomes of catheterization laboratories in different centers have not been defined. We have demonstrated that death and other catastrophic outcomes are significantly associated with procedural volume. However, the association between procedural volume and less severe adverse events was much less strong. We propose to study the association between procedural volume and risk of failure to rescue (i.e., the ability to avoid catastrophic outcome given an adverse event), and in so doing introduce it to as a novel outcome measure in the field. We propose to leverage a multi-center clinical registry, the IMproving Pediatric and Adult Treatment (IMPACT) registry to accomplish this aim. Second, economic cost is not only a surrogate marker of clinical outcome, but also an independent measure of the efficiency of healthcare delivery. We propose to establish benchmarks for the economic cost of catheterization procedures, and to study the factors influencing cost. To accomplish this aim, we will use a multi-center administrative database, the Pediatric Health Information System (PHIS) database. Third, patient-reported outcomes, such as health-related quality of life (HR-QOL) represent an important aspect of health that is not captured in traditional physician reported outcomes (and moreover are not included in multicenter registries and databases). They also represent an important aspect (along with cost) of comparative effectiveness research. We propose to perform a single center cohort study of children undergoing catheterization to define the effect of cardiac catheterization on HR-QOL, and to determine the factors (modifiable and non-modifiable) that influence it. Together, these three aims illuminate different outcomes associated with cardiac catheterization in children. By combining these novel techniques, the applicant hopes to begin to define the factors that influence health and well-being of children undergoing catheterization and set the groundwork for studies that will test interventions to improve the quality of care for children requiring cardiac catheterization.